section 1 DE Flashcards
how are elements arranged in the periodic table?
in order of atomic number, and in groups and periods
which are groups, which are periods?
groups - vertical columns
periods - horizontal columns (rows)
what does the group of an element correspond to?
number of atoms in outer shell
what is the name for group 0
noble gases
name for group 7?
halogens
name for group 1?
alkali metals
which groups are metals?
the left side of the periodic table and then it is like steps going down (1 at a time) from g3-g7 e.g., boron is a non metal but aluminum is and so forth
why do elements in the same group have similar properties?
they have the same number of electrons in their outer shell
what are the main group elements?
elements on the periodic table in columns 1, 2, and 13 to 18
why do noble gases not readily react?
The atoms of noble gases already have complete outer shells, so they have no tendency to lose, gain, or share electrons. This is why the noble gases are inert and do not take part in chemical reactions.
how can you use the acid-base character of oxides to classify elements as metals or non-metals
Acid-base character of oxides: Metal oxides are basic (bases-alkali), while nonmetal oxides are acidic
how can you use the electrical conductivity to classify elements as metals or non-metals
Metals are good conductors of electricity, while nonmetals are poor conductors.
what are all non metals?
acidic and they dissolve in water to form solutions with a pH of less than 7
what are all metals
metal oxides are basic and they dissolve in water to form solutions with a pH of above than 7
physical properties of metals?
Metals are shiny, malleable, ductile, and have high melting and boiling points.
